Sex

"Sex" may include many things, from intimate touching to vaginal or anal intercourse.

These terms are often used:

Sexual contact may involve genital touching, skin-to-skin contact, mutual masturbation, mouth-to-genital contact (oral sex), or sexual intercourse.
Sexual intercourse can refer to vaginal sex (penetration of the vagina), oral sex (mouth to penis, vagina, or anus), or anal sex (penetration of the anus).